The acclaimed writer-and-actor will return to the BBC sci-fi drama to write two episodes for the upcoming eighth series, which will see Peter Capaldi make his debut as the Twelfth Doctor.
Mark said during a recent promotional trip to Brazil on behalf of BBC Worldwide: "I am writing for Peter Capaldi - two episodes, in fact."
The 'Sherlock' writer has previously written six episodes of 'Doctor Who' and appeared in a 2007 episode of the series as Professor Lazarus.
Mark also penned BBC Two's 'Doctor Who' origins drama 'An Adventure in Space and Time', which aired last November as part of the show's 50th anniversary celebrations.
The writer recently praised Peter Capaldi's portrayal of the Doctor and feels he will bring new energy to the role.
He said: "Peter has a very different energy to Matt Smith and to David Tennant. He's older which changes everything ... it's amazing what a change does!
"Matt was sublime and I was very sorry to see him go, but it's also great to have a change, as it has always been with the Doctor."